Reference Manual error
Hey SmithMicro, just though you guys might like to know there's a slight error in the reference manual that's apparently been there since at least PP2012. It's in the chapter on the Material room in the listing of the items you'll find in the advanced tab.
The OBJECT LIST description names the following Options: Props, Lights, Figures, and Background. One thing you fail to point out is that Figures options will only be present IF there's a figure in the actual scene. (I checked). And that same description doesn't mention the Atmospheres option at all. It is mentioned later in the Root Nodes section though.